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1.
J Exp Bot ; 75(1): 274-299, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37804484

RESUMO

Catharanthus roseus leaves produce a range of monoterpenoid indole alkaloids (MIAs) that include low levels of the anticancer drugs vinblastine and vincristine. The MIA pathway displays a complex architecture spanning different subcellular and cell type localizations, and is under complex regulation. As a result, the development of strategies to increase the levels of the anticancer MIAs has remained elusive. The pathway involves mesophyll specialized idioblasts where the late unsolved biosynthetic steps are thought to occur. Here, protoplasts of C. roseus leaf idioblasts were isolated by fluorescence-activated cell sorting, and their differential alkaloid and transcriptomic profiles were characterized. This involved the assembly of an improved C. roseus transcriptome from short- and long-read data, IDIO+. It was observed that C. roseus mesophyll idioblasts possess a distinctive transcriptomic profile associated with protection against biotic and abiotic stresses, and indicative that this cell type is a carbon sink, in contrast to surrounding mesophyll cells. Moreover, it is shown that idioblasts are a hotspot of alkaloid accumulation, suggesting that their transcriptome may hold the key to the in-depth understanding of the MIA pathway and the success of strategies leading to higher levels of the anticancer drugs.


Assuntos
Antineoplásicos , Catharanthus , Plantas Medicinais , Alcaloides de Triptamina e Secologanina , Plantas Medicinais/metabolismo , Catharanthus/genética , Catharanthus/metabolismo , Antineoplásicos/metabolismo , Alcaloides de Triptamina e Secologanina/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
2.
Sensors (Basel) ; 23(11)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37299854

RESUMO

Physical fatigue reduces productivity and quality of work while increasing the risk of injuries and accidents among safety-sensitive professionals. To prevent its adverse effects, researchers are developing automated assessment methods that, despite being highly accurate, require a comprehensive understanding of underlying mechanisms and variables' contributions to determine their real-life applicability. This work aims to evaluate the performance variations of a previously developed four-level physical fatigue model when alternating its inputs to have a comprehensive view of the impact of each physiological variable on the model's functioning. Data from heart rate, breathing rate, core temperature and personal characteristics from 24 firefighters during an incremental running protocol were used to develop the physical fatigue model based on an XGBoosted tree classifier. The model was trained 11 times with different input combinations resulting from alternating four groups of features. Performance measures from each case showed that heart rate is the most relevant signal for estimating physical fatigue. Breathing rate and core temperature enhanced the model when combined with heart rate but showed poor performance individually. Overall, this study highlights the advantage of using more than one physiological measure for improving physical fatigue modelling. The findings can contribute to variables and sensor selection in occupational applications and as the foundation for further field research.


Assuntos
Bombeiros , Humanos , Fadiga , Monitorização Fisiológica , Eficiência , Frequência Cardíaca
3.
Int J Mol Sci ; 24(10)2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37240070

RESUMO

Alpha-aminoterminal acetyltransferase B (NatB) is a critical enzyme responsible for acetylating the aminoterminal end of proteins, thereby modifying approximately 21% of the proteome. This post-translational modification impacts protein folding, structure, stability, and interactions between proteins which, in turn, play a crucial role in modulating several biological functions. NatB has been widely studied for its role in cytoskeleton function and cell cycle regulation in different organisms, from yeast to human tumor cells. In this study, we aimed to understand the biological importance of this modification by inactivating the catalytic subunit of the NatB enzymatic complex, Naa20, in non-transformed mammal cells. Our findings demonstrate that depletion of NAA20 results in decreased cell cycle progression and DNA replication initiation, ultimately leading to the senescence program. Furthermore, we have identified NatB substrates that play a role in cell cycle progression, and their stability is compromised when NatB is inactivated. These results underscore the significance of N-terminal acetylation by NatB in regulating cell cycle progression and DNA replication.


Assuntos
Proteínas de Saccharomyces cerevisiae , Animais , Humanos , Proteínas de Saccharomyces cerevisiae/metabolismo , Domínio Catalítico , Saccharomyces cerevisiae/metabolismo , Processamento de Proteína Pós-Traducional , Replicação do DNA , Acetilação , Acetiltransferases/metabolismo , Mamíferos/metabolismo
4.
Int J Environ Health Res ; : 1-13, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37820712

RESUMO

The aims were to highlight noise levels on board and the health effects of noise on seafarers. Data was collected from multiple databases: PubMed, Web of Science, Scopus, and Ebsco Host. Initially, the search resulted in a total of 197 articles, 16 were chosen. Several ships were found which most sailors had noise-induced hearing loss (NIHL) (n = 6). The engine room has been defined as having the highest level of noise. In addition, noise exposure was associated with hearing loss, tinnitus, sleep disturbances, communication difficulties, poor concentration, dizziness, depression, anxiety, headache, fatigue, and stress. Noise exposure is not the only factor that causes health problems: the duration of exposure while working, years of career as a maritime worker, age, lifestyle habits (smoking, alcohol consumption), and even hobbies related to loud sound (such as concert/disco attendance, listen to loud music, etc.) were associated with the adverse health effects experienced by seafarers.

5.
J Neurochem ; 163(2): 74-93, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35950924

RESUMO

Microglia are tissue-resident macrophages responsible for the surveillance, neuronal support, and immune defense of the brain parenchyma. Recently, the role played by microglia in the formation and function of neuronal circuits has garnered substantial attention. During development, microglia have been shown to engulf neuronal precursors and participate in pruning mechanisms while, in the mature brain, they influence synaptic signaling, provide trophic support and shape synaptic plasticity. Recently, studies have unveiled different microglial characteristics associated with specific brain regions. This emerging view suggests that the maturation and function of distinct neuronal circuits may be potentially associated with the molecular identity microglia adopts across the brain. Here, we review and summarize the known role of these cells in the thalamus, hippocampus, cortex, and cerebellum. We focus on in vivo studies to highlight the characteristics of microglia that may be important in the remodeling of these neuronal circuits and in relation to neurodevelopmental and neuropsychiatric disorders.


Assuntos
Microglia , Plasticidade Neuronal , Encéfalo/fisiologia , Hipocampo/fisiologia , Microglia/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios , Sinapses/fisiologia
6.
Apoptosis ; 27(5-6): 368-381, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35362903

RESUMO

Proteins of the Bcl-2 protein family, including pro-apoptotic Bax and anti-apoptotic Bcl-xL, are critical for mitochondrial-mediated apoptosis regulation. Since yeast lacks obvious orthologs of Bcl-2 family members, heterologous expression of these proteins has been used to investigate their molecular and functional aspects. Active Bax is involved in the formation of mitochondrial outer membrane pores, through which cytochrome c (cyt c) is released, triggering a cascade of downstream apoptotic events. However, when in its inactive form, Bax is largely cytosolic or weakly bound to mitochondria. Given the central role of Bax in apoptosis, studies aiming to understand its regulation are of paramount importance towards its exploitation as a therapeutic target. So far, studies taking advantage of heterologous expression of human Bax in yeast to unveil regulation of Bax activation have relied on the use of artificial mutated or mitochondrial tagged Bax for its activation, rather than the wild type Bax (Bax α). Here, we found that cell death could be triggered in yeast cells heterologoulsy expressing Bax α with concentrations of acetic acid that are not lethal to wild type cells. This was associated with Bax mitochondrial translocation and cyt c release, closely resembling the natural Bax function in the cellular context. This regulated cell death process was reverted by co-expression with Bcl-xL, but not with Bcl-xLΔC, and in the absence of Rim11p, the yeast ortholog of mammalian GSK3ß. This novel system mimics human Bax α regulation by GSK3ß and can therefore be used as a platform to uncover novel Bax regulators and explore its therapeutic modulation.


Assuntos
Citocromos c , Saccharomyces cerevisiae , Ácido Acético , Animais , Apoptose/genética , Proteínas de Transporte , Citocromos c/genética , Citocromos c/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Mamíferos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
7.
Sensors (Basel) ; 23(1)2022 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-36616791

RESUMO

Physical fatigue is a serious threat to the health and safety of firefighters. Its effects include decreased cognitive abilities and a heightened risk of accidents. Subjective scales and, recently, on-body sensors have been used to monitor physical fatigue among firefighters and safety-sensitive professionals. Considering the capabilities (e.g., noninvasiveness and continuous monitoring) and limitations (e.g., assessed fatiguing tasks and models validation procedures) of current approaches, this study aimed to develop a physical fatigue prediction model combining cardiorespiratory and thermoregulatory measures and machine learning algorithms within a firefighters' sample. Sensory data from heart rate, breathing rate and core temperature were recorded from 24 participants during an incremental running protocol. Various supervised machine learning algorithms were examined using 21 features extracted from the physiological variables and participants' characteristics to estimate four physical fatigue conditions: low, moderate, heavy and severe. Results showed that the XGBoosted Trees algorithm achieved the best outcomes with an average accuracy of 82% and accuracies of 93% and 86% for recognising the low and severe levels. Furthermore, this study evaluated different methods to assess the models' performance, concluding that the group cross-validation method presents the most practical results. Overall, this study highlights the advantages of using multiple physiological measures for enhancing physical fatigue modelling. It proposes a promising health and safety management tool and lays the foundation for future studies in field conditions.


Assuntos
Bombeiros , Humanos , Exercício Físico , Fadiga , Aprendizado de Máquina , Frequência Cardíaca/fisiologia
8.
Sensors (Basel) ; 21(21)2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34770556

RESUMO

The emergence of physiological monitoring technologies has produced exceptional opportunities for real-time collection and analysis of workers' physiological information. To benefit from these safety and health prognostic opportunities, research efforts have explored the applicability of these devices to control workers' wellbeing levels during occupational activities. A systematic review is proposed to summarise up-to-date progress in applying physiological monitoring systems for occupational groups. Adhering with the PRISMA Statement, five databases were searched from 2014 to 2021, and 12 keywords were combined, concluding with the selection of 38 articles. Sources of risk of bias were assessed regarding randomisation procedures, selective outcome reporting and generalisability of results. Assessment procedures involving non-invasive methods applied with health and safety-related goals were filtered. Working-age participants from homogeneous occupational groups were selected, with these groups primarily including firefighters and construction workers. Research objectives were mainly directed to assess heat stress and physiological workload demands. Heart rate related variables, thermal responses and motion tracking through accelerometry were the most common approaches. Overall, wearable sensors proved to be valid tools for assessing physiological status in working environments. Future research should focus on conducting sensor fusion assessments, engaging wearables in real-time evaluation methods and giving continuous feedback to workers and practitioners.


Assuntos
Transtornos de Estresse por Calor , Acelerometria , Frequência Cardíaca , Humanos , Monitorização Fisiológica , Local de Trabalho
9.
J Strength Cond Res ; 35(6): 1628-1635, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34027921

RESUMO

ABSTRACT: Matos, F, Ferreira, B, Guedes, J, Saavedra, F, Reis, VM, and Vilaça-Alves, J. Effect of rest interval between sets in the muscle function during a sequence of strength training exercises for the upper body. J Strength Cond Res 35(6): 1628-1635, 2021-The objective of this study was to observe the ideal recovery time between sets and exercises, for both chest and back, which allowed for maintaining muscle function with the initial load previously established. Sixty young men recreationally trained in strength training (ST) were divided into 2 groups: (a) 30 subjects were included in the GC group (the group that performed ST for the chest) and (b) 30 subjects were included in the GB group (the group that performed ST for the back). Each group was submitted to 3 experimental sessions, performing an ST sequence with 3 sets of 8 repetition maximum: GC performed a chest barbell press (CBP), an inclined CBP, and a chest butterfly; GB performed a lat pull-down, a back row, and a shoulder extension on the high pulley. The experimental sessions differed in rest time between sets performed (60, 90, and 120 seconds). For both groups in each sequence, significantly higher numbers of repetitions were observed with the rest time of 120 seconds relative to the rest time of 90 seconds (p = 0.004), 120 seconds in relation to the rest time of 60 seconds (p = 0.001), and in the rest interval of 90 seconds in relation to the rest time of 60 seconds (p < 0.0001). The results showed that 120 seconds was sufficient to maintain muscle function and perform the total number of repetitions per set. The data seem to show that for the ST methodology applied, it is not appropriate to assume that a certain relative intensity will translate into a similar number of repetitions in different exercises, especially with shorter rest intervals such as 60 and 90 seconds.


Assuntos
Treinamento Resistido , Exercício Físico , Humanos , Masculino , Força Muscular , Músculo Esquelético , Descanso , Levantamento de Peso
10.
J Neuroinflammation ; 17(1): 120, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32299465

RESUMO

BACKGROUND: Glioblastomas are the most common and lethal primary brain tumors. Microglia, the resident immune cells of the brain, survey their environment and respond to pathogens, toxins, and tumors. Glioblastoma cells communicate with microglia, in part by releasing extracellular vesicles (EVs). Despite the presence of large numbers of microglia in glioblastoma, the tumors continue to grow, and these neuroimmune cells appear incapable of keeping the tumor in check. To understand this process, we analyzed gene expression in microglia interacting with glioblastoma cells. METHODS: We used RNASeq of isolated microglia to analyze the expression patterns of genes involved in key microglial functions in mice with glioblastoma. We focused on microglia that had taken up tumor-derived EVs and therefore were within and immediately adjacent to the tumor. RESULTS: We show that these microglia have downregulated expression of genes involved in sensing tumor cells and tumor-derived danger signals, as well as genes used for tumor killing. In contrast, expression of genes involved in facilitating tumor spread was upregulated. These changes appear to be in part EV-mediated, since intracranial injection of EVs in normal mice led to similar transcriptional changes in microglia. We observed a similar microglial transcriptomic signature when we analyzed datasets from human patients with glioblastoma. CONCLUSION: Our data define a microgliaGlioblastoma specific phenotype, whereby glioblastomas have hijacked gene expression in the neuroimmune system to favor avoiding tumor sensing, suppressing the immune response, clearing a path for invasion, and enhancing tumor propagation. For further exploration, we developed an interactive online tool at http://www.glioma-microglia.com with all expression data and additional functional and pathway information for each gene.


Assuntos
Neoplasias Encefálicas/metabolismo , Regulação Neoplásica da Expressão Gênica , Glioblastoma/metabolismo , Microglia/metabolismo , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/patologia , Feminino , Técnicas de Introdução de Genes/métodos , Glioblastoma/genética , Glioblastoma/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/patologia , Carga Tumoral/fisiologia
11.
J Exp Bot ; 71(12): 3664-3677, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32133499

RESUMO

The F-bZIP transcription factors bZIP19 and bZIP23 are the central regulators of the zinc deficiency response in Arabidopsis, and phylogenetic analysis of F-bZIP homologs across land plants indicates that the regulatory mechanism of the zinc deficiency response may be conserved. Here, we identified the rice F-bZIP homologs and investigated their function. OsbZIP48 and OsbZIP50, but not OsbZIP49, complement the zinc deficiency-hypersensitive Arabidopsis bzip19bzip23 double mutant. Ectopic expression of OsbZIP50 in Arabidopsis significantly increases plant zinc accumulation under control zinc supply, suggesting an altered Zn sensing in OsbZIP50. In addition, we performed a phylogenetic analysis of F-bZIP homologs from representative monocot species that supports the branching of plant F-bZIPs into Group 1 and Group 2. Our results suggest that regulation of the zinc deficiency response in rice is conserved, with OsbZIP48 being a functional homolog of AtbZIP19 and AtbZIP23. A better understanding of the mechanisms behind the Zn deficiency response in rice and other important crops will contribute to develop plant-based strategies to address the problems of Zn deficiency in soils, crops, and cereal-based human diets.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica , Oryza , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Zinco/metabolismo
12.
Plant Physiol ; 171(4): 2371-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27356972

RESUMO

Plant specialized metabolism often presents a complex cell-specific compartmentation essential to accomplish the biosynthesis of valuable plant natural products. Hence, the disclosure and potential manipulation of such pathways may depend on the capacity to isolate and characterize specific cell types. Catharanthus roseus is the source of several medicinal terpenoid indole alkaloids, including the low-level anticancer vinblastine and vincristine, for which the late biosynthetic steps occur in specialized mesophyll cells called idioblasts. Here, the optical, fluorescence, and alkaloid-accumulating properties of C. roseus leaf idioblasts are characterized, and a methodology for the isolation of idioblast protoplasts by fluorescence-activated cell sorting is established, taking advantage of the distinctive autofluorescence of these cells. This achievement represents a crucial step for the development of differential omic strategies leading to the identification of candidate genes putatively involved in the biosynthesis, pathway regulation, and transmembrane transport leading to the anticancer alkaloids from C. roseus.


Assuntos
Catharanthus/metabolismo , Separação Celular/métodos , Citometria de Fluxo/métodos , Alcaloides de Triptamina e Secologanina/metabolismo , Vimblastina/metabolismo , Catharanthus/citologia , Células do Mesofilo/citologia , Células do Mesofilo/metabolismo , Folhas de Planta/citologia , Folhas de Planta/metabolismo
13.
Hum Mol Genet ; 23(23): 6286-301, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24990149

RESUMO

MicroRNAs (miRNAs) have emerged as a class of small, endogenous, regulatory RNAs that exhibit the ability to epigenetically modulate the translation of mRNAs into proteins. This feature enables them to control cell phenotypes and, consequently, modify cell function in a disease context. The role of inflammatory miRNAs in Alzheimer's disease (AD) and their ability to modulate glia responses are now beginning to be explored. In this study, we propose to disclose the functional role of miR-155, one of the most well studied immune-related miRNAs in AD-associated neuroinflammatory events, employing the 3xTg AD animal model. A strong upregulation of miR-155 levels was observed in the brain of 12-month-old 3xTg AD animals. This event occurred simultaneously with an increase of microglia and astrocyte activation, and before the appearance of extracellular Aß aggregates, suggesting that less complex Aß species, such as Aß oligomers may contribute to early neuroinflammation. In addition, we investigated the contribution of miR-155 and the c-Jun transcription factor to the molecular mechanisms that underlie Aß-mediated activation of glial cells. Our results suggest early miR-155 and c-Jun upregulation in the 3xTg AD mice, as well as in Aß-activated microglia and astrocytes, thus contributing to the production of inflammatory mediators such as IL-6 and IFN-ß. This effect is associated with a miR-155-dependent decrease of suppressor of cytokine signaling 1. Furthermore, since c-Jun silencing decreases the levels of miR-155 in Aß-activated microglia and astrocytes, we propose that miR-155 targeting can constitute an interesting and promising approach to control neuroinflammation in AD.


Assuntos
Doença de Alzheimer/patologia , Encéfalo/metabolismo , MicroRNAs/metabolismo , Neurônios/metabolismo , Doença de Alzheimer/imunologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Astrócitos/metabolismo , Encéfalo/patologia , Linhagem Celular , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/patologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/metabolismo , Proteína 1 Supressora da Sinalização de Citocina , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Regulação para Cima
14.
Eur J Immunol ; 44(3): 856-66, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24227629

RESUMO

The activation of TLRs by microbial molecules triggers intracellular-signaling cascades and the expression of cytokines such as IL-10. Il10 expression is tightly controlled to ensure effective immune responses, while preventing pathology. Maximal TLR-induction of Il10 transcription in macrophages requires signaling through the MAPKs, ERK, and p38. Signals via p38 downstream of TLR4 activation also regulate IL-10 at the post-transcriptional level, but whether this mechanism operates downstream of other TLRs is not clear. We compared the regulation of IL-10 production in TLR2 and TLR4-stimulated BM-derived macrophages and found different stability profiles for the Il10 mRNA. TLR2 signals promoted a rapid induction and degradation of Il10 mRNA, whereas TLR4 signals protected Il10 mRNA from rapid degradation, due to the activation of Toll/IL-1 receptor domain-containing adaptor inducing IFN-ß (TRIF) and enhanced p38 signaling. This differential post-transcriptional mechanism contributes to a stronger induction of IL-10 secretion via TLR4. Our study provides a molecular mechanism for the differential IL-10 production by TLR2- or TLR4-stimulated BMMs, showing that p38-induced stability is not common to all TLR-signaling pathways. This mechanism is also observed upon bacterial activation of TLR2 or TLR4 in BMMs, contributing to IL-10 modulation in these cells in an infection setting.


Assuntos
Interleucina-10/genética , Ativação de Macrófagos , Macrófagos/imunologia , Macrófagos/metabolismo , Processamento Pós-Transcricional do RNA , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Bactérias/imunologia , Ativação Enzimática , Feminino , Regulação da Expressão Gênica , Macrófagos/microbiologia , Camundongos , Camundongos Knockout , Estabilidade de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Tristetraprolina/deficiência , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
15.
Mol Phylogenet Evol ; 89: 160-70, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25937559

RESUMO

Here we reconstruct the evolutionary history of Micromeria in the Canary Islands using eight nuclear markers. Our results show two centers of diversification for Micromeria, one in the eastern islands Gran Canaria and Lanzarote, the other in the western islands, Tenerife, La Palma and El Hierro. Suggested directions of inter-island colonization are the following: Gran Canaria to Lanzarote and La Gomera; Tenerife to La Palma (from the paleoisland of Teno), to El Hierro (from the younger, central part), and to La Gomera and Madeira (from the paleoislands). Colonization of La Gomera probably occurred several times from Gran Canaria and Tenerife. The taxonomic implications of these results are discussed. Incongruence among the different markers was evaluated and, using next generation sequencing, we investigated if this incongruence is due to gene duplication.


Assuntos
Núcleo Celular/genética , Ilhas , Lamiaceae/genética , Filogenia , Duplicação Gênica/genética , Marcadores Genéticos/genética , Variação Genética/genética , Sequenciamento de Nucleotídeos em Larga Escala , Filogeografia , Portugal , Análise de Sequência de DNA , Espanha
16.
BMC Cancer ; 13: 169, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23548132

RESUMO

BACKGROUND: KRAS is an EGFR effector in the RAS/RAF/ERK cascade that is mutated in about 40% of metastatic colorectal cancer (mCRC). Activating mutations in codons 12 and 13 of the KRAS gene are the only established negative predictors of response to anti-EGFR therapy and patients whose tumors harbor such mutations are not candidates for therapy. However, 40 to 60% of wild-type cases do not respond to anti-EGFR therapy, suggesting the involvement of other genes that act downstream of EGFR in the RAS-RAF-MAPK and PI3K-AKT pathways or activating KRAS mutations at other locations of the gene. METHODS: DNA was obtained from a consecutive series of 201 mCRC cases (FFPE tissue), wild-type for KRAS exon 2 (codons 12 and 13). Mutational analysis of KRAS (exons 3 and 4), BRAF (exons 11 and 15), and PIK3CA (exons 9 and 20) was performed by high resolution melting (HRM) and positive cases were then sequenced. RESULTS: One mutation was present in 23.4% (47/201) of the cases and 3.0% additional cases (6/201) had two concomitant mutations. A total of 53 cases showed 59 mutations, with the following distribution: 44.1% (26/59) in KRAS (13 in exon 3 and 13 in exon 4), 18.6% (11/59) in BRAF (two in exon 11 and nine in exon 15) and 37.3% (22/59) in PIK3CA (16 in exon 9 and six in exon 20). In total, 26.4% (53/201) of the cases had at least one mutation and the remaining 73.6% (148/201) were wild-type for all regions studied. Five of the mutations we report, four in KRAS and one in BRAF, have not previously been described in CRC. BRAF and PIK3CA mutations were more frequent in the colon than in the sigmoid or rectum: 20.8% vs. 1.6% vs. 0.0% (P=0.000) for BRAF and 23.4% vs. 12.1% vs. 5.4% (P=0.011) for PIK3CA mutations. CONCLUSIONS: About one fourth of mCRC cases wild-type for KRAS codons 12 and 13 present other mutations either in KRAS, BRAF, or PIK3CA, many of which may explain the lack of response to anti-EGFR therapy observed in a significant proportion of these patients.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Éxons , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Adulto , Sequência de Bases , Classe I de Fosfatidilinositol 3-Quinases , Neoplasias Colorretais/tratamento farmacológico , Receptores ErbB/antagonistas & inibidores , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Taxa de Mutação , Metástase Neoplásica , Técnicas de Amplificação de Ácido Nucleico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas p21(ras) , Temperatura de Transição , Resultado do Tratamento
17.
Rev Bras Med Trab ; 21(1): e2023947, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37197333

RESUMO

The different areas and work environments in the hospital sector have a complex set of occupational risk factors that can negatively impact the health of pregnant workers. Illness among this workforce results in sick leave due to work-related diseases and pregnancy, with high absenteeism. The main objective of this study was to review the available literature on the gestational and occupational risks to which pregnant health workers are exposed, causes of absenteeism, and issues related to maternity protection and work in the hospital sector. The authors used online databases to identify papers published in English from 2015 to 2020, based on the PRISMA Extension for Scoping Reviews and three steps of Snowballing. The study reviewed 18 peer-reviewed scientific articles that address pregnancy, work, absenteeism, and maternity protection. Most studies used a quantitative approach (12) and cohort studies in particular (6). The distribution of articles by themes was as follows: pregnancy, health and safety at work (11); pregnancy, health conditions, and absenteeism (13); and work and maternity protection (10). Some inferences were possible from the themes raised. However, the results revealed a gap and the need for specific studies for healthcare workers in the hospital sector, focusing on maternity. This review contributes to more in-depth studies on developing programs, actions, and legislation to protect maternity in hospital working environments.


As diferentes áreas e ambientes de trabalho do setor hospitalar apresentam uma complexidade de fatores de risco que podem impactar negativamente a saúde das trabalhadoras grávidas. O adoecimento dessa força de trabalho resulta em afastamentos por doenças relacionadas ao trabalho e à gravidez, com alto absenteísmo. O objetivo principal deste estudo foi revisar a literatura disponível sobre os riscos gestacionais e ocupacionais a que estão expostas as trabalhadoras de saúde grávidas, causas de absenteísmo e questões relacionadas à proteção da maternidade e do trabalho no setor hospitalar. Bases de dados online foram usadas para identificar artigos em inglês publicados de 2015 a 2020, com base no PRISMA Extension for Scoping Reviews e três etapas de snowballing. Este estudo incluiu 18 artigos científicos revisados por pares que abordam questões relativas à gravidez, absenteísmo e proteção à maternidade no trabalho. A maioria dos estudos utilizou abordagem quantitativa (12), com ênfase nos estudos de coorte (6). Distribuição dos artigos por temas: gravidez, saúde e segurança no trabalho (11); gravidez, intercorrências e absenteísmo (13); e proteção ao trabalho e maternidade (10). Algumas inferências foram possíveis a partir dos temas levantados. No entanto, os resultados evidenciaram a lacuna e a necessidade de estudos específicos para trabalhadores de saúde do setor hospitalar, com enfoque na maternidade. Esta revisão pode contribuir para estudos mais aprofundados sobre o desenvolvimento de programas, ações e legislações de proteção à maternidade no ambiente de trabalho do setor hospitalar.

18.
Neuron ; 111(21): 3435-3449.e8, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37918358

RESUMO

Interleukin-4 (IL-4) is a type 2 cytokine with pleiotropic functions in adaptive immunity, allergies, and cognitive processes. Here, we show that low levels of IL-4 in the early postnatal stage delineate a critical period in which microglia extensively prune cerebellar neurons. Elevating the levels of this cytokine via peripheral injection, or using a mouse model of allergic asthma, leads to defective pruning, permanent increase in cerebellar granule cells, and circuit alterations. These animals also show a hyperkinetic and impulsive-like phenotype, reminiscent of attention-deficit hyperactivity disorder (ADHD). These alterations are blocked in Il4rαfl/fl::Cx3cr1-CreER mice, which are deficient in IL-4 receptor signaling in microglia. These findings demonstrate a previously unknown role for IL-4 during a neuroimmune critical period of cerebellar maturation and provide a first putative mechanism for the comorbidity between allergic disease and ADHD observed in humans.


Assuntos
Interleucina-4 , Microglia , Animais , Humanos , Cerebelo , Encéfalo , Citocinas
19.
Immunology ; 135(1): 73-88, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22043967

RESUMO

Innate immunity constitutes the first line of defence against both external and endogenous threats in the brain, and microglia cells are considered key mediators of this process. Recent studies have shown that microRNAs (miRNAs) may play a determinant role in the regulation of gene expression during innate immune responses. The major goal of this work was to investigate the contribution of a specific miRNA - miR-155 - to the modulation of the microglia-mediated immune response. For this purpose, in vitro studies were performed in N9 microglia cells to evaluate changes in the levels of this miRNA following microglia activation. A strong up-regulation of miR-155 expression was observed following microglia exposure to lipopolysaccharide, which was consistent with a decrease in the levels of the suppressor of cytokine signalling 1 (SOCS-1) protein, a key inhibitor of the inflammatory process and a predicted target of miR-155. The miR-155 knockdown by anti-miRNA oligonucleotides up-regulated SOCS-1 mRNA and protein levels and significantly decreased the production of nitric oxide and the expression of inflammatory cytokines and inducible nitric oxide synthase. Finally, treatment of neuronal primary cultures with conditioned medium obtained from microglia cells, in which miR-155 was inhibited before cell activation, decreased inflammatory-mediated neuronal cell death. Overall, our results show that miR-155 has a pro-inflammatory role in microglia and is necessary for the progression of the immune response through the modulation of SOCS-1, suggesting that, in a chronic inflammatory context, miR-155 inhibition can have a neuroprotective effect.


Assuntos
Citocinas/imunologia , MicroRNAs/imunologia , Microglia/imunologia , Óxido Nítrico/imunologia , Proteínas Supressoras da Sinalização de Citocina/imunologia , Animais , Células Cultivadas , Citocinas/biossíntese , Regulação para Baixo/efeitos dos fármacos , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Camundongos , MicroRNAs/biossíntese , Microglia/metabolismo , Óxido Nítrico/biossíntese , Proteína 1 Supressora da Sinalização de Citocina , Regulação para Cima/efeitos dos fármacos
20.
Methods Mol Biol ; 2505: 191-202, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35732946

RESUMO

Transcriptional regulation is a central piece of the highly valuable monoterpenoid indole alkaloid pathway of C. roseus , and the ultimate tool for its understanding and manipulation. Here, we describe the adaptation of the TARGET methodology to identify specific and genome-wide leaf targets of C. roseus candidate transcription factors (TFs).


Assuntos
Catharanthus , Plantas Medicinais , Catharanthus/genética , Catharanthus/metabolismo , Regulação da Expressão Gênica de Plantas , Alcaloides Indólicos/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Medicinais/genética , Plantas Medicinais/metabolismo
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